Aiming at the formation control problem of single-leader multi-UAV systems with a communication delay,a controller is designed based on the consistency control theory,so that the system can still make each system state consistent under a certain communication delay,and form the expected formation.Firstly,the dynamic model of each UAV in the system is established,some basic assumptions are made,and the controller with undetermined parameters are designed according to the consistency control theory.Secondly,a new system is obtained through variable substitution and mathematical deformation,which transforms the formation control problem of the original system into the asymptotic stability problem of the low-order system.Finally,the Lyapunov-Krasovskii function is designed,and the sufficient conditions for the system to achieve consistency are derived by combining linear matrix inequalities.The simulation results show that the system can form the expected time-varying formation under the condition of time delay when the given conditions are met.